Not surprisingly, Lars von Trier’s two-part movie “Nymphomaniac” is difficult to evaluate right from Volume One. The filmmaker’s exploration of sex addict Joe (Charlotte Gainsbourg) is being released in two parts, and a criticism of part one must carry with it the caveat that it is only the first half of a single story. Thankfully, “Volume One” succeeds by building anticipation for the coming second half while serving as a fascinating character drama in its own right.

Joe is first introduced covered in fresh bruises and lying in the middle of the street. It is unclear whether she is even alive until a good Samaritan, Seligman (Stellan Skarsgard), helps her up and takes her back to his apartment to patch her up. The rest of the plot is told through flashbacks, as Joe tells her savior the story of her lifelong sexual odyssey. Joe craves anonymous sexual encounters but recoils away from anything resembling a real human relationship. Yet her story, broken up into chapters, focuses on the people that have left an impression despite her best efforts: her father (Christian Slater), her first love (Shia LeBeouf) and the scorned wife of one of her faceless suitors (Uma Thurman), among others.

Newcomer Stacy Martin, who plays young Joe, is the standout in the cast. A lesser movie might relegate Martin to a passive window dressing that allows the older actress to do the bulk of the character work. Instead, Martin actually has more screen time than Gainsbourg and develops her own character without putting her performance at odds with her elder counterpart’s. Her performance doesn’t just rely on Gainsbourg’s narration to serve as character development. Instead, Martin manages to stand out by emphasizing the youthfulness of her character while still showing Gainsbourg’s emotional detachment.

The other two remarkable performances in the film are from Uma Thurman and, surprisingly enough, Shia LaBeouf. As Jerome, the mechanic who takes Joe’s virginity and then makes a surprise appearance in her life years later, LaBeouf is uncompromising in his portrayal of an unlikeable brute. Thurman only gets a single scene, but makes it count, dominating the screen as the wife who doesn’t quite know how to react when she meets her husband’s mistress. Though clearly emotionally broken, Thurman’s character demands Joe’s attention and makes her realize that she doesn’t exist in an emotional void.

Von Trier, who also wrote the script, presents the film through a series of flashbacks, each of them playing as its own mini-drama. Each memory has its own dramatic arc, and they’re carefully linked together to create a detailed picture of this woman’s life. “Nymphomaniac” has been highly publicized since its initial announcement for its explicit sexual depictions, and while its multiple pornographic sequences don’t feel entirely necessary, they don’t detract from the quality of the film.

The teaser for Volume 2 that plays during the credits points to some of the more extreme content that von Trier has saved for the second half. If that preview is to be believed, Volume One is tame by comparison, focusing more on Joe’s psychological state than her sexual activities. While this story could easily fall apart in its second segment, “Nymphomaniac: Volume One” is promising in its dedication to the characters and the story rather than the shock value of the material.